Contributions
Abstract: P348
Type: Poster
Abstract Category: Clinical aspects of MS - 5 Epidemiology
Background: Relapsing-remitting multiple sclerosis (RRMS) is the most common disease course of multiple sclerosis (MS) patients. Levels of disease activity among RRMS patients vary, with a proportion of RRMS patients experiencing high disease activity (HDA). It is critical to understand the association between disease activity and disease progression over time.
Objectives: Measure the association between disease activity and Kurtzke Expanded Disability Status Scale (EDSS)-based confirmed disability progression (CDP) in RRMS patients.
Methods: A cohort of 3,212 adult RRMS patients enrolled in the Swedish population-based MS register during 1996-2015 (inclusive) was followed from the date of disease modifying drug (DMD) initiation until CDP, DMD discontinuation, or last recorded visit. Time to first 6-month CDP was analysed using a Cox proportional hazards model, where CDP was defined as an incremental increase of at least 1 EDSS point for patients with baseline EDSS≤5.5 or an increase of at least 0.5 for those with baseline EDSS>5.5, with a confirmed increased EDSS score 3-6 months later. All other patients were censored with no event at the end of follow-up. Estimates were adjusted for age, sex, initiation year, and type of DMD. Patients were classified into three subgroups at DMD initiation: active disease, defined as the presence of a relapse or T2 lesion, HDA-R defined as 2 relapses observed within 1 year of each other, or Highly Active RRMS (HA-RRMS) defined as 9 or more T2 lesions or at least 1 gadolinium-enhanced T1 lesion. Patients not fulfilling any subgroup criteria were classified as low activity (LA).
Results: Across the four patient groups, mean (standard deviation) age ranged from 34 (10) to 37 (10) years and percentage of females ranged from 69% to 75%. Median EDSS score at DMD initiation was 1.5 for all groups except HA-RRMS, where the median was 2.0. Interferon was the most commonly initiated DMD but was considerably less common in the HA-RRMS group. Relative to the LA group, the adjusted hazard ratio of CDP was 1.04 (p=0.82), 1.07 (p=0.74), and 1.08 (p=0.72) for patients with active disease, HDA-R, and HA-RRMS, respectively.
Conclusions: In this initial analysis, no evidence of differences in disease progression was observed among patients with varying levels of disease activity. Analyses are on-going and upcoming results will be enhanced with marginal structural modelling to account for time-dependent confounding.
Disclosure: This study was sponsored by EMD Serono Inc, a business of Merck KGaA, Darmstadt, Germany.
TS received honoraria for consultancy, funding for travel and compensation for serving on scientific advisory boards from Biogen Idec Inc; speaker honoraria from Novartis.
KG provided consulting services to Merck as an employee of PAREXEL.
BA provided consulting services to Merck as an employee of PAREXEL.
JH has received honoraria for serving on advisory boards for Biogen, Sanofi-Genzyme and Novartis and speaker's fees from Biogen, Novartis, Merck-Serono, Bayer-Schering, Teva and Sanofi-Genzyme. He has served as P.I. for projects, or received unrestricted research support from, BiogenIdec, Merck-Serono, TEVA, Sanofi-Genzyme and Bayer-Schering. His MS research is funded by the Swedish Research Council and the Swedish Brain foundation.
SW is an employee of EMD Serono, Inc., a business of Merck KGaA, Darmstadt, Germany
Abstract: P348
Type: Poster
Abstract Category: Clinical aspects of MS - 5 Epidemiology
Background: Relapsing-remitting multiple sclerosis (RRMS) is the most common disease course of multiple sclerosis (MS) patients. Levels of disease activity among RRMS patients vary, with a proportion of RRMS patients experiencing high disease activity (HDA). It is critical to understand the association between disease activity and disease progression over time.
Objectives: Measure the association between disease activity and Kurtzke Expanded Disability Status Scale (EDSS)-based confirmed disability progression (CDP) in RRMS patients.
Methods: A cohort of 3,212 adult RRMS patients enrolled in the Swedish population-based MS register during 1996-2015 (inclusive) was followed from the date of disease modifying drug (DMD) initiation until CDP, DMD discontinuation, or last recorded visit. Time to first 6-month CDP was analysed using a Cox proportional hazards model, where CDP was defined as an incremental increase of at least 1 EDSS point for patients with baseline EDSS≤5.5 or an increase of at least 0.5 for those with baseline EDSS>5.5, with a confirmed increased EDSS score 3-6 months later. All other patients were censored with no event at the end of follow-up. Estimates were adjusted for age, sex, initiation year, and type of DMD. Patients were classified into three subgroups at DMD initiation: active disease, defined as the presence of a relapse or T2 lesion, HDA-R defined as 2 relapses observed within 1 year of each other, or Highly Active RRMS (HA-RRMS) defined as 9 or more T2 lesions or at least 1 gadolinium-enhanced T1 lesion. Patients not fulfilling any subgroup criteria were classified as low activity (LA).
Results: Across the four patient groups, mean (standard deviation) age ranged from 34 (10) to 37 (10) years and percentage of females ranged from 69% to 75%. Median EDSS score at DMD initiation was 1.5 for all groups except HA-RRMS, where the median was 2.0. Interferon was the most commonly initiated DMD but was considerably less common in the HA-RRMS group. Relative to the LA group, the adjusted hazard ratio of CDP was 1.04 (p=0.82), 1.07 (p=0.74), and 1.08 (p=0.72) for patients with active disease, HDA-R, and HA-RRMS, respectively.
Conclusions: In this initial analysis, no evidence of differences in disease progression was observed among patients with varying levels of disease activity. Analyses are on-going and upcoming results will be enhanced with marginal structural modelling to account for time-dependent confounding.
Disclosure: This study was sponsored by EMD Serono Inc, a business of Merck KGaA, Darmstadt, Germany.
TS received honoraria for consultancy, funding for travel and compensation for serving on scientific advisory boards from Biogen Idec Inc; speaker honoraria from Novartis.
KG provided consulting services to Merck as an employee of PAREXEL.
BA provided consulting services to Merck as an employee of PAREXEL.
JH has received honoraria for serving on advisory boards for Biogen, Sanofi-Genzyme and Novartis and speaker's fees from Biogen, Novartis, Merck-Serono, Bayer-Schering, Teva and Sanofi-Genzyme. He has served as P.I. for projects, or received unrestricted research support from, BiogenIdec, Merck-Serono, TEVA, Sanofi-Genzyme and Bayer-Schering. His MS research is funded by the Swedish Research Council and the Swedish Brain foundation.
SW is an employee of EMD Serono, Inc., a business of Merck KGaA, Darmstadt, Germany